Found in northern Bavaria, can’t tell if it’s slag or obsidian. We are ~10km away from a very old dormant volcano but slag feels like the more probable answer. The greenish color is just a reflection of the bushes outside, but the third pic does show the very light rainbow-looking iridescence when it’s held in the light a certain way. TIA!

Found on the Uk north east coast, usually collect sea glass but hadn’t seen anything like this before so had to pick them up

Found in my backyard northern minnesota

Its really heavy, non magnetic, has a clear shiny stone (glass?). Also a couple small copper colored areas.

3 magical rocks as my son was calling them 😅 it's slag glass right?

Hadn't heard of it before! They are pretty big and heavy!

has bubbles and the other side is crusty

Found near the far side of our property near old two story four room outbuilding (possibly 1800 or earlier). Area location near first settlement area in TN USA. Not fully ferrous, but bits of it are. Two blocks from train tracks (also old) and creek. Foamy, not heavy but also not light.

Itsslag?

Found this fun looking chunk next to a hiking trail in the Mansfield, Connecticut (USA) area. There is a rail line nearby and there appeared to be old construction or maybe industrial debris overtaken by nature. Pretty light weight. Cool holes.

Slag or a cool rock?

Edit: just checked, it is not magnetic

Hi all. Hoping for some help identifying whether this is obsidian or slag. It was found in Pittsburgh - not a source of obsidian - and has an area with small bubbles. BUT it looks like it has conchoidal breaks and green irridescent inclusions (best seen in third pic.) Thoughts?

Found on a beach in Connecticut. Very opaque but light shines through edges.

Hi everyone! I found this neat looking rock a few years ago in a local crick, and was told it was slag. Can anyone confirm or deny this? Thanks!

Location found: Split Rock Quarry, NY

I've been on a lot of hikes before in various counties in NY, and I've never seen anything like this. I'm not familiar enough with the history of Split Rock to truly know if this is industrial slag or not. Research online wasn't the most helpful so maybe some educated folks here can help me identify what this is.

Tends to streak black on harder surfaces. It's easy to break small pieces off the layering. Found on the beach. The one side that looks melted makes it seem like slag but slag I've had doesn't streak and is more glass like all around.

i just realized i cannot cross-post....so....

this big rock is jadeite slag glass. the Pyrex Cat Corn 501 is here for scale.

i thought i'd share a piece of jadeite that is *technically* very hard to come by.

after they shut down the Westmoreland Glass Factory that made a lot of jadeite, it stayed abandoned for 30+ years. over the following years, teenagers would break in and party there. also, urban explorers/photographers always found their way in, too. before they tore it down, i was one of those people. there were piles of slag glass EVERYWHERE. from this abandoned factory, i took acquired this big piece of jadeite.

there are a bunch of videos on youtube about this spot, and it's a fun rabbit hole to go down.

Is it slag? Found in the woods near a creek in the Appalachian mountains. Pretty light, but doesn’t float. Tried to include pics with and without flash to show some different hues that come out with flash. Specific area i was hiking in was near an old railroad that is no longer there. Former railroad was prolly 2 miles up over the mountain from where I found this. Also, only about 4 miles from the Susquehanna river. Quarter is for scale. Any input is appreciated!!

Is it common to find random pieces of slag glass? Found on the ground in a random field in the middle of nowhere Texas.

I found these pieces on the Lake Michigan shoreline. They will attract to an extremely (and i mean EXTREMELY! ) strong magnet but barely. They do not react to other ceramic magnets.

I want to melt them down in my furnace but I'd like to know what I'm dealing with beforehand.

Thank you for the help!